Chapter 8, Problem 104A

Interpretation Introduction

(a)

Interpretation:

Lewis structure of ${\text{H}}_{\text{2}}\text{S}$ needs to be explained.

Concept introduction:

Lewis structure is also called as Lewis dot structure. In this structure, valence electrons are represented by dot symbol around the central atom. This structure shows the bonding between molecule and the lone pairs which may occur in the molecule.

Answer to Problem 104A

The Lewis structure of ${\text{H}}_{\text{2}}\text{S}$ is as follows:

Explanation of Solution

Determine the valence electrons which are available for bonding in ${\text{H}}_{\text{2}}\text{S}$. It contains one sulfur (6 valence electrons) and 2 hydrogen atoms (1 electron for each hydrogen). Total number of valence electron is $6+1\times 2=8$. There are 8 valence electrons for bonding. Total number of bonding pair is $\frac{8\text{electrons}}{2\text{electrons}}=4\text{pairs}$. Hence, 4 pairs of electrons are available for bonding.

Remaining bonding pairs are $4\text{pairs}-2\text{pairs}\text{used}=2\text{pairs}$.

The remaining pairs-lone pair-must be added to the terminal atoms or the central atom. Hence, the Lewis structure of ${\text{H}}_{\text{2}}\text{S}$ as follows:

Interpretation Introduction

(b)

Interpretation:

Lewis structure of ${\text{BF}}_4^{-}$ needs to be explained.

Concept introduction:

Lewis structure is also called as Lewis dot structure. In this structure, valence electrons are represented by dot symbol around the central atom. This structure shows the bonding between molecule and the lone pairs which may occur in the molecule.

Answer to Problem 104A

The Lewis structure of ${\text{BF}}_4^{-}$ is-

Explanation of Solution

Determine the valence electrons which are available for bonding in ${\text{BF}}_4^{-}$. It contains one boron and 4 fluorine atoms. Valance electron of B is 3 and F is 7. Hence, total number of valence electron is $3+4\times 7+1=32$. There are 32 valence electrons for bonding. Total number of bonding pair is $\frac{32\text{electrons}}{2\text{electrons}}=16\text{pairs}$. Hence, 16 pairs of electrons are available for bonding.

Remaining bonding pairs are $16\text{pairs}-4\text{pairs}\text{used}=12\text{pairs}$.

The remaining pairs-lone pair-must be added to the terminal atoms or the central atom. Hence, the Lewis structure of ${\text{BF}}_4^{-}$ as follows:

Interpretation Introduction

(c)

Interpretation:

Lewis structure of ${\text{SO}}_{\text{2}}$ needs to be explained.

Concept introduction:

Lewis structure is also called as Lewis dot structure. In this structure, valence electrons are represented by dot symbol around the central atom. This structure shows the bonding between molecule and the lone pairs which may occur in the molecule.

Answer to Problem 104A

The Lewis structure of ${\text{SO}}_{\text{2}}$ is-

Explanation of Solution

Determine the valence electrons which are available for bonding in ${\text{SO}}_{\text{2}}$. It contains one S and 2 oxygen atoms. Valence electron of S is 6 and O is 6. Hence, total number of valence electron is $6+2\times 6=18$. There are 18 valence electrons for bonding. Total number of bonding pair is $\frac{18\text{electrons}}{2\text{electrons}}=9\text{pairs}$. Hence, 9 pairs of electrons are available for bonding.

Remaining bonding pairs are $9\text{pairs}-2\text{pairs}\text{used}=6\text{pairs}$.

Either to the terminal atoms or the central atom, the remaining pairs that is lone pair must be added. Hence, the Lewis structure of ${\text{SO}}_{\text{2}}$ as follows:

Two lone pairs from each O is taken to form double bond with S.

Interpretation Introduction

(d)

Interpretation:

Lewis structure of ${\text{SeCl}}_{\text{2}}$ needs to be explained.

Concept introduction:

Lewis structure is also called as Lewis dot structure. In this structure, valence electrons are represented by dot symbol around the central atom. This structure shows the bonding between molecule and the lone pairs which may occur in the molecule.

Answer to Problem 104A

The Lewis structure of ${\text{SeCl}}_{\text{2}}$ is-

Explanation of Solution

Determine the valence electrons which are available for bonding in ${\text{SeCl}}_{\text{2}}$. It contains one Se and 2 Cl atoms. Valence electron of Se is 6 and Cl is 7. Hence, total number of valence electron is $6+2\times 7=20$. There are 20 valence electrons for bonding. Total number of bonding pair is $\frac{20\text{electrons}}{2\text{electrons}}=10\text{pairs}$. Hence, 10 pairs of electrons are available for bonding.

Remaining bonding pairs are $10\text{pairs}-2\text{pairs}\text{used}=8\text{pairs}$.

Either to the the terminal atoms or the central atom, the remaining pairs that is lone pairs must be added. Hence, the Lewis structure of ${\text{SeCl}}_{\text{2}}$ as follows: